Alkener och Alkyner

katalytisk hydrogenering av alken (med Pd/H2)

dubbelbindningen omvandlas till enkelbindning

alkene reacts with H2 has in the presence of a metal catalyst (Pd,Pt, Ni)

each carbon gets one hydrogen added

1. the alkene absorbs into the the metal surface Pd

2. h2 splits into 2 hydrogens on the surface

3. both hydrigens are added to the same side of the bond

this is a syn addition because both H attach to the same side

syn addition

anti addition

either both H attach overifrån eller underifrån

Elektrofil addition av HX (vätehalid) to alkene

Hbr for example

Markovnikov applies here, where H goes to the least substituted carbon and X to the more substituted carbon.

so double bond breaks, H attached to one like and X to the other

Elektrofil hydratisering av alken

syrakatalyserad hydratisering (hydratisering av alken, addition of H2O)

the pi bond attacks hydrogen and attached to it making a carbocation,

markovnikov

the reagent can be H2SO4 or H3PO4 which are acids

then water is added

OH is added to the bomd and a hydrogen leaves

Elektrofil addition av halogen (Br2 or Cl2)

gives trans products meaning the bromines attach on opposite sides

The ion may react with other nucleophiles in this case the methoxy group because ethanol is the solvent it exist in a much larger amount than br

and the nucleophile attacks the most substituted carbon

katalytisk hydrogenering av alkyner

with Lindlar/H2 turns into alkene

with Pd/H2 turns into alkane

elektrofil additikn av vätehalid HX

markovnikov

triple bond breaks one attaches to Br and an H

and the other also to a Br and an H

Deprotonering och nukleofil attack

terminala alkyner är svagt sura (på grund av elektrondraganfe trippelbindningen

1. Terminal alkane loses its H and becomes a negatively charged carbon whixh then acts as a nucleophile. how this happens is that a strong base like NaH2 pulls of the H

2. then the nucleophilic attack happens and attaches an alkyl group the X leaves